I've finally run out of my first tank of CO2 and am not sure where to get it filled. I think I remember reading something about different grades of CO2 but not the specifics. Does anyone know what I need to look for and what to avoid? What kinds of places have the CO2 that I need?

Welding shops, fire extinguisher refillers, and paintball stores all fill Co2 tanks usually. For me, I called every store in the area that I could think of and National Welders ended up being the best deal. $16 for a 20 lb exchange. Be sure to shop around because the price varies widely. Some places wanted more than $50 for the same 20 lbs.

As far as the 'grades', I think the only difference is what container it comes in, straight steel versus glass lined, for example. Also, I think most places only stock one type and go ahead and use 'food grade' so they can sell to more people.

EDIT: I was pretty wrong about the grades part. I found this on another forum:

Quote:

FYI, i work in this industry. There are two main types of CO2, "Beverage Grade" and then everything else. The difference between the two is that beverage grade CO2 has less TRS, and HC, gasses in it, such as H2S, CS2 ect... Basically stinky gasses that make your soda smell like farts. Anyway, almost all CO2 that is used is beverage grade CO2. The stuff that isn't beverage grade gets turned into Dry Ice. Most plants that have CO2 as a byproduct run it through a lot of filtering processes to make it nice and clean "beverage grade". Most Welding CO2 is Beverage Grade as places that make CO2 always try to make the best stuff they can. Only if something breaks or doesn't work correctly do they have non-beverage grade CO2.

If you do a swapout vs. a refill just make sure you don't give up your shiny new tank for an old beat-up one... nothing wrong with a dinged up one but if you did pay for a nice new one it's best to ask for that one to be filled...

If you do a swapout vs. a refill just make sure you don't give up your shiny new tank for an old beat-up one... nothing wrong with a dinged up one but if you did pay for a nice new one it's best to ask for that one to be filled...

Very good point. In my case, I paid for a beat up ugly one on craigslist, so I'm happy to swap an empty ugly for a full ugly!